Current methods for retrieving unmanned watercraft vehicles at sea involve manual handling of the watercraft after attachment thereof to an elongated tow line extended from a retrieval ship and subsequent manual detachment of the tow line from the towed vehicle for shipboard crane transfer of the watercraft onto the ship. Such retrieval methods are very cumbersome and manpower intensive. It is therefore an important object of the present invention to provide for such towing delivery of watercraft to a retrieval ship while avoiding the problematic manual processing involved. 